The present invention relates to display devices. In particular, the present invention relates to a method and apparatus for modifying the size and/or resolution of displayed information corresponding to changes in the size of a display area of the display device.
One major criterion for functionality of portable devices such as personal digital assistants (PDAs) is size. Designers constantly battle with the trade off between compactness of the device, thus enhancing portability, and optimum size of the device""s user interface such as the display screen. Indeed, the more compact the portable device, the smaller the display screen size for users. While most consumers desire multi-functional portable devices that are compact and lightweight, they also tend to prefer as large a display screen size as possible for these portable devices. However, the display screen size is limited by the physical dimensions of the portable devices.
Through recent advances in display technology, displays which are flexible in nature and thus able to be folded have been developed. For example, Philips Electronics, NV of the Netherlands has introduced display technology using plastic polymer semiconductors rather than silicon, potentially paving the way for foldable, flexible display devices. In such devices, the display may comprise an active-matrix of a predetermined pixel count (such as 4,096 pixels which translate to 64 pixels square), where each pixel is controlled by a thin-film transistor (TFT) based on a polymer semiconductor.
A foldable display device is configured to fold in a similar manner as a wallet. In this manner, when the device is being carried around by a user, it may easily fit into the user""s shirt or jacket pocket. When in use, the user may unfold the display device such that the display screen size of the device is many times larger than the folded size. For example, a tri-fold might provide a viewable screen size approximately three times the width of the screen in the folded state, thus, providing the largest display screen size when the device is in a completely unfolded state. Using a single screen with flexible circuitry, display devices may be folded a number of times for portability (though increasing the thickness of the device), and unfolded partially or completely by the user when in use.
The Institute for Complex Engineered Systems (ICES) at Carnegie Mellon University has introduced the concept of foldable displays to meet the needs of, for example, professionals and consumers who are more likely to operate the portable device in a setting outside the confines of an office or a home. The foldable display device from ICES is configured such that the displayed content changes depending on the number of times the display is folded. When the display screen size of the display device is relatively small (i.e., in a folded state), only applications which do not require large display area may be operated. When the display screen size of the foldable display device is increased (i.e., in an unfolded state), then corresponding applications which are preferably viewed on a larger screen (for example, web browsing using a browser application such as Microsoft Internet Explorer or Netscape Communicator) are operated. Additional information on this technology may be found at the following URL:
http://www.ices.cmu.edu/design/foldabledisplay.html (last accessed Oct. 1, 2001).
Conventional foldable display devices have several disadvantages. Some foldable display devices are not operational in the folded state. When these display devices are folded, the entire screen is enclosed within the folded display device. For such devices, the ability to fold the display device is merely for convenience to allow the user to more easily transport the display device. Other foldable display devices significantly cut off the display content when in the folded state. Still other foldable display devices may show an undesirable line which extends across the seam of the fold.
In view of the foregoing, it would be desirable to have a foldable display device which is capable of dynamically adjusting the size and/or resolution of the displayed information in response to modifications to the display area resulting from folding and/or unfolding operations.
The present invention provides an adjustable display device which includes a plurality of display segments defining an adjustable size of a display device for displaying data, and a detection mechanism (e.g., a switch array) operatively coupled to the plurality of display segments. The detection mechanism is configured to detect a change in size of the display device by displacement of at least one of the plurality of display segments and to generate a corresponding detection signal. The adjustable display device further includes a controller operatively coupled to the detection mechanism and configured to (1) receive the detection signal; (2) adjust displayed data of the display device in response to the detection signal; and (3) display the adjusted displayed data on one or more of the display segments.
In one aspect, the displacement of the display segments may include unfolding or folding the display device such that the size of the display device is changed by at least one display segment. Alternatively, display segment displacement may include detaching or attaching at least one display segment of the display device. Furthermore, the detection mechanism may include a plurality of sensors, each sensor operatively coupled to a respective one of the plurality of display segments and configured to generate a detection signal when the corresponding display segment is displaced.
In at least one embodiment, displayed data may be changed in size by an amount that is substantially proportional to the change in the size of the display device, and/or a resolution of displayed data may be adjusted corresponding to the change in the size of the display device. Numerous other aspects are provided, as are methods and computer program products. Each inventive computer program product may be carried by a medium readable by a computer (e.g., a carrier wave signal, a floppy disk, a hard drive, a random access memory, etc.).
Other objects, features and advantages of the present invention will become more fully apparent from the following detailed description, the appended claims and the accompanying drawings.